Blowing nozzle for the refining of metals



May 27, 1958 .1. AUER BLOWING NOZZLE FOR THE REFINING 0F METALS Filed May 19, 1955 United States BLOWING NOZZLE FOR THE REFINING OF METALS Josef Auer, Oberhausen, Germany, assignor to Hiittenwerk Oberhausen Aktiengesellschaft, Oberhansen, Germany The present invention relates to an apparatus for delivering a fluid into contact with a relatively large body of molten metal and, more particularly, concerns a tuyere or lance for refining metals by introducing a blast from above beneath the surface of a metal bath or by blowing the blast onto the surface of a metal bath. It has been suggested heretofore to surround such a tuyere or lance by a cooling jacket divided intotwo concentric annular chambers by a thermally insulating wall extending nearly to the mouth of the tuyere or lance, the cooling agent preferably entering the inner annular chamber and being discharged from the outer annular chamber. In this way, the heated cooling water flowing back from the mouth of the tuyere or lance does not increase the temperature of the inflowing water. While this tuyere or lance is characterized by a long service life, it has, however, the drawback that with the customarily employed moderate pressures, only a relatively small quantity of blast can be blown from the tuyere per time unit. This is due to the fact that only a relatively small part of the total volume of the tuyere is available as a central supply pipe for the supply of the blast. Consequently the reatent O fining period requires a correspondingly long time. On 1 the other hand, it is not practical to combine a plurality of such water-cooled tuyeres or lances to form a bundle of tuyeres because, aside from the diiiiculty of handling such a bulky and voluminous structure, the constunption of cooling agent would be unfeasible economically. If it were intended to blow larger quantities of blast per time unit by blowing the blast through the tuyere at a higher pressure, an additional expenditure of energy would be required for the compression of the blast, in addition to the employment of auxiliary devices which would considerably increase the cost of the process. Furthermore, there would exist the danger that a portion of the oxygen would not be taken up by the melt so that the blast is incompletely utilized.

It is, therefore, an object of the present invention to provide a liquid-cooled tuyere or lance which will overcome the above mentioned drawbacks.

It is another object of this invention to provide a liquid-cooled tuyere or lance for refining metals, which will be characterized by a low consumption of cooling water and Without being subject to destruction will make it possible per time unit to blow such great quantities of blast that in the'time required for refining, the heat losses of the melt by radiation will be comparatively low.

It is another object of this invention to provide a tuyere or lance which will make it possible to bring the blast into contact with the melt in such a way that contact between the reacting constituents will be as intimate as possible to thereby bring about a complete utilization of the blast without excessive loss of metal.

It is a still further object of this invention to provide a tuyere or lance of the type set forth in the preceding paragraph which will be simple in construction, resistant to heat and rough handling and will have a small total cross section only while the cross section available ice for the feeding of the blast will be rather large with regard to the cross section of the cooling water jacket.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawing in which:

Fig. l is a longitudinal section of a tuyere or lance according to the invention, the head of the tuyere being shown partly in elevation and partly in section.

Fig. 2 is an end view of the device shown in Fig. 1 when viewing the same in the direction of the arrow 11.

Fig. 3 is a cross section of the device taken along the line III-ill of Fig. 1.

Fig. 4 is a cross section of the device of Fig. 1 taken along the line IVIV thereof.

General arrangement The tuyere or lance according to the present invention which is provided with a mouth piece having a plurality of outlet orifices for the blast, is characterized primarily in that the feeding conduit for the blast to the mouth of the tuyere divides the interior of the tuyere or lance into a central supply conduit means or chamber for the feeding of a cooling agent to the mouth of the tuyere, and into an outer substantially coaxial return conduit or chamber of annular cross section for the return of the cooling agent from the feeding conduit for the blast adjacent said mouth. The device according to the invention is furthermore characterized in that the feeding conduit or supply conduit means for the blast is near the mouth of the tuyere or lance provided with openings or passages through which the cooling agent can pass from the said central chamber or supply conduit means to the outer annular chamber or return conduit for the return of the cooling agent. In this way, it is possible, due to the simple and space-saving construction of the device, to supply to the bath surprisingly large quantities of blast per time unit, while the consumption of cooling agent is small and the total cross section of the tuyere is relatively small.

Structural arrangement Referring now to the drawing in detail, the tuyere or lance shown therein consists primarily of two concentric tubular bodies arranged one within the other. The outer tubular body is designated with the reference numeral 1, whereas the inner tubular body is generally designated with the reference numeral 2. The inner wall surface of the tubular body 1 defines with the opposite wall surface of the inner tubular body a jacket or return conduit 19 for cooling water, which conduit is tightly closed at its upper end by means of a tubular header 4. The tubular body 1 is furthermore provided with a lateral discharge connection 5 for discharging the cooling water from said return conduit. A plate 6 is inserted into the lower end of the tubular body 1 and forms the bottom wall of the tuyere or lance.

According to Fig. 1, the inner tubular body 2 consists of two pipes 7 and 8 placed coaxially one within the other in spaced relationhip from each other, thereby confining with each other a feeding conduit of annular cross section for feeding the blast to the mouth of the tuyere or lance. The inner wall surface of the tube 8 defines a central chamber or feeding conduit 3 for conveying the cooling agent to the mouth of the tuyere. Thus, the outer annular chamber or conduit 19 for the return of the cooling agent is separated from the feeding conduit 3 for the cooling agent by the feeding conduit for the blast.

The pipe or tube 7 communicates at its upper end with the header 4, while the tube 8 the inner wall surface of which confines the cooling water conveying unit 3 extime.

pip-e17 of greater cross section so that a distributing chamber 9 is formed. .Directly above titer-bottom plate 6, the distributing chamber 9 is traversed by radial channels 39 separated at the top and sides from saidchamber 9 by walls 11 and 12 respectively. Between thechan; nels 10, the distributing chamber 9' extends forward; t

the bottom plate ti which at these points is provided a large number of apertures13 (Fig l). The external side of the tube 7 is provided with guiding or spacer fins i i (Figs. 1 and 3) Which in-surethat the tube 7 will occupy a substantially concentric position in the tubular body 1. While the blast or refining means may be fed to the distributing chamber directly through the above mentioned feeding conduit defined by the tubes .7 and 8; the refiningmeans may also be fed to the distributing chamber through a plurality of closely adiacently and annularly arranged tubes lSinserted into the annular chamber or conduit confined by the tubes 7 and 8. 'Thc upper ends of said tubes lead into the header 4, 'while thelower ends of said tubes 15 communicate with the distributing chamber 9.

The blast is conveyed to the header 4 through the feeding pipe 13 and the tubes 16, and through the tubes 15.

manner conveyed to" the rest of the bath wherebymthe 7 additional partition of thermally insulating material thereconductor as for instance copper.-

the melt and thus benefits the meta'lbath while simul- V taneonsly the cooling means itself is cool-ed. This heat exchange can be accentuated by filling the chamber between the tubes 15 and the tube 7 with a good heat The cooling effect uponthe mouth of the tuyere 'is,increased the fact that the cooling agenton its way from' tube 8through channels 10 into the annular chamber 19.

experiences a sharp change in its direction of flow wheret by it is rendered turbulent. Similarly, for obtaining a good cooling. effect, the interior surface of; the tubular body It is roughened to avoid laminar'flow of the. cooling agent. A turbulent flow of the cooling'agent ma'y also indicated in the lower portion of. Fig. l.

1 is increased in an advantageous manner; However,

care is to be taken that'the corrugations a're'not so pro nounced that dead corners will form in which heated cooling means would be retained.

To protect the; immersed portion of the tubular body 1, especially that'portion which is adjacent the mouth of the tuyere, from' corrosion by the molten bath and the combustion products formed during the refining process, that outer surface of thertubular. bodyl which comes into I contact with the bath is provided with beads 21-which danger 'ofthermaldamage to the tuyere isconsiderably reduced. Furthermore, the blast brought into a particu 'larly intimate contact with themelt, is quickly absorbed by the same land is utilized completely in a minimum of When annularlyiarranged blast feedingtubes 15 are employed, those portions oftheutubes 7 and 8 which are located between the header 4 and the distributing chamher 9 may be omitted.-

The cooling agent," preferably water,"- is conveyed. to the mouth of the tuyere or distributing chamber 9, by

tub-5 hQw Y g the? portion of tube 8 is omit.-

sponding feeding conduit for the cooling; agent is formed The tuyere or lance according to the inventioncan therein.

thereforebe immersed relatively deeply into the I bath. 'without damage;

Bysutficiently deeply immersing the tuyere into the bath and due to the presence of alarge reaction surface, the advantage; is obtained that the iferrous oxide'forrned during the refining. process has on its way to the, surface lot the bath .sufiicient opportunity to .ted which is located between 'parts t and 9, the corre-' by; the substantially cylindrical passage confined by the.

inwardly directed outer wall surface portions ofsaid tubes 15. I I r e H 1 5 91 9 and the annular chamber; 19 between'the tubular body 1 and the tubular body 7; or tube '15, and

'is discharged from the tuyere'through', the conneotion.5., The arrangement of the supplyof cooling wateralong the axis of the tuyere, i e. within theic'ondu'it 3 or ,within. the central chamber confined by;the tubes 15,;and the discharge of the coolingwa'ter. alongthe outside of tube The coolingfagent then fiows through th 7 or the outwardly directed wall portions of tubesTiSh and reaches the mouthlof the tuyere, wheresthe maximum give up its oxygento other ingredients in theiron in the bath such as-silicon, carbon;v phosphorus etc. Therefore, by employing a tuyere' or lanceaccording to'the present invention "a slag of .low iron content is obtained," i. e., a satisfactory yield-of iron. Furthermore,;in contrast to all heretofore known devices for. refining by. blowing the blast, upon or into the bath, a con'siderablereduction in the formation of .vaporized. ferrous oxidein form of'the known brown smokeis obtainedwhichfact is duef-to the g relativelygreat; depth of immersion andthe avoidance of anoverheat'ed reaction zonefi Inasmuch as by'means of the tuyereaccord'ingto. the invention it is, possible with a small consumptionof. coolinguagent and a small total It is, of courseyunderstood thatthe present invention is, by no means, limited togtheparticular construction 'shown'in, the drawing but also comprises anymod-ifica- -tions within the scope of the appended claims.

What I'claim' is: Y LA twyerfor delivering a gaseous blast'into-contact with 'a relatively large body of molteometah;whichcomprises in combination:' first tubulat means a bottom member connected to one end'of said tubular means and temperature prevails, practically without increase in tem+ pera'ture so that the best possible cooling eifect ofqthe month of the tuyere is obtained; The employmentrof an.

having an inner surface substantially perpendicular to the longitudinaliaxis of said tubular meansjsaid tubuiar means having an outlet at the other end thereof, second 3 tubular means coaxial with but in spaced relationship to said first tubular means, said second tubular means having one end connected to said bottom member in liquidtight condition and having the other end thereof arranged for connection with a source of cooling liquid, third tubular means interposed between said first and second tubular means and arranged in spaced relationship thereto, said third tubular means having one end connected to said bottom member in liquid-tight condition and having the other end thereof arranged for connection with a source of gaseous fluid, and tunnel-like passage means partly formed by the inner surface of said bottom memher and comprising top and side walls extending in a straight direction substantially perpendicular to the lon gitudinal axis of said second tubular means through the walls of said second and third tubular means and establishing communication between the interior of said second tubular means and the annular chamber confined by the interior wall of said first tubular means and the exterior wall of said third tubular means, those areas of said bottom member which are confined by said second and third tubular means and located outside said tunnel-like passage means being provided with passages extending through said bottom member and having their axes substantially perpendicular thereto.

2. In combination in a twyer for delivering a gaseous blast into contact with a relatively large body of molten metal: a first tubular member having one end provided with a plate forming the bottom of said first tubular member and having its inner surface substantially perpendicular to the longitudinal axis of said tubular member, said first tubular member having an outlet at its other end, a second tubular member coaxial with said first tubular member and spaced therefrom, said second tubular member having one end connected to the central portion of said bottom in liquid-tight condition and having its other end arranged for connection with a source of cooling liquid, at third tubular member substantially coaxial with and interposed between said first and second tubular members and arranged in spaced relationship thereto, said third tubular member having one end connected to said bottom in liquid-tight condition and having its other end arranged for connection with a source of gaseous fluid, and a plurality of tunnel-like passage means extending in a liquid-tight manner through the walls of said second and third tubular members at the bottom of said first tubular member in radial direction from that end of said second tubular member which is adjacent said bottom for establishing communication between the interior of said second tubular member and the annular chamber confined by the interior wall of said first tubular member and the exterior wall of said third tubular member, said tunnel-like passage means having substantially straight top and side walls and having their inner bottom surface formed by a portion of the inner surface of said plate, those areas of said plate which are confined by said second and third tubular members and the outside of the side walls of said tunnel-like passage means being provided with passages extending through said plate and having their axes substantially parallel to the longitudinal axis of said third tubular member.

3. An apparatus according to claim 2, in which that end portion of said second tubular member which is adjacent the plate forming the bottom of said first tubular member flares outwardly in a bell-shaped manner.

4. A twyer for delivering a gaseous blast into contact with a relatively large body of molten metal, which comprises in combination: first tubular means, a bottom member connected to one end of said tubular means and having a plane inner surface substantially perpendicular to the longitudinal axis of said tubular means, said tubular means having an outlet at the other end thereof, second tubular means coaxial with but in spaced relationship to said first tubular means, said second tubular means having one end connected to said bottom member in liquid-tight condition and having the other end thereof arranged for connection with a source of cooling liquid, third tubular means interposed between said first and second tubular means and arranged in spaced relationship thereto, said third tubular means having a first portion of substantially uniform outer diameter spaced from said bottom member and having a second portion of increased diameter leading from said first portion to said'bottom member and being connected thereto in a liquid-tight condition, a plurality of tubes arranged in the annular chamber confined by the inner wall of said first portion of said third tubular means and the outer wall of said second tubular means, one end of each of said tubes leading into the interior of the second portion of said third tubular means and the other end of said tubes being arranged for connection with a source of gaseous fluid, and tunnel-like passage means extending at said bottom member through the walls of said second tubular means and of the second portion of said third tubular means and establishing communication between the interior of said second tubular means and the annular chamber confined by the interior wall of said first tubular means and the exterior wall of said third tubular means, said tunnellike passage means comprising substantially straight top and side walls and having their inner bottom surface formed by a portion of the plane inner surface of said bottom member, those areas of said bottom member which are confined by the outside wall of said second tubular means and the inside wall of the second portion of said third tubular means and also by the outside of the side walls of said passage means being provided with passages extending through said bottom member and having their axes substantially perpendicular to the inner plane surface thereof.

References Cited in the file of this patent UNITED STATES PATENTS 165,561 Goodsell July 13, 1875 250,769 Watson Dec. 13, 1881 1,312,474 Fisk Aug. 5, 1919 1,844,194 Maltitz Feb. 9, 1932 1,848,079 Johnson et a1 Mar. 1, 1932 1,870,511 Hopkins Aug. 9, 1932 1,910,724 Unden May 23, 1933 2,145,649 Fox Jan. 31, 1939 2,333,654 Lellep Nov. 9, 1943 2,546,937 Wyandt et al. Mar. 27, 1951 FOREIGN PATENTS 400,793 Great Britain Nov. 2, 1933 

1. A TWYER FOR DELIVERING A GASEOUS BLAST INTO CONTACT WITH A RELATIVELY LARGE BODY OF MOLTEN METAL, WHICH COMPRISES IN COMBINATION. FIRST TUBULAR MEANS, A BOTTOM MEMBER CONNECTED TO ONE END OF SAID TUBULAR MEANS AND HAVING AN INNER SURFACE SUBSTANTIALLY PREPENDICULAR TO THE LONGITUDINAL AXIS OF SAID TUBULAR MEANS, SAID TUBULAR MEANS HAVING AN OUTLET AT THE OTHER END THEREOF, SECOND TUBULAR MEANS COASIAL WITH BUT IN SPACED RELATIONSHIP TO SAID FIRST TUBULAR MEANS, SAID SECOND TUBULAR MEANS HAVING ONE END CONNECTED TO SAID BOTTOM MEMBER IN LIQUIDTIGHT CONDITION AND HAVING THE OTHER END THEREOF ARRANGED FOR CONNECTION WITH A SOURCE OF COOLING LIQUID, THIRD TUBULAR MEANS INTERPOSED BETWEEN SAID FIRST AND SECOND TUBULAR MEANS AND ARRANGED IN SPACED RELATIONSHIP THERETO, SAID THIRD TUBULAR MEANS HAVING ONE END CONNECTED TO SAID BOTTOM MEMBER IN LIQUID-TIGHT CONNECTION AND HAVING THE OTHER END THEREOF ARRANGED FOR CONNECTION WITH A SOURCE OF GASEOUS FLUID, AND TUNNEL-LIKE PASSAGE MEANS PARTLY FORMED BY THE INNER SURFACE OF SAID BOTTOM MEMBER AND COMPRISING TOP AND SIDE WALLS EXTENDING IN A STRAIGHT DIRECTION SUBSTANTIALLY PERPENDICULAR TO THE LONGITUDINAL AXIS OF SAID SECOND TUBULAR MEANS THROUGH THE WALLS OF SAID SECOND AND THIRD TUBULAR MEANS AND ESTABLISHING COMMUNICATION BETWEEN THE INTERIOR OF SAID SECOND TUBULAR MEANS AND THE ANNULAR CHAMBER CONFINED BY THE INTERIOR WALL OF SAID FIRST TUBULAR MEANS AN D THE EXTERIOR WALL OF SAID THIRD TUBULAR MEANS, THOSE AREAS OF SAID BOTTOM MEMBER WHICH ARE CONFINED BY SAID SECOND AND THIRD TUBULAR MEANS AND LOCATED OUTSIDE SAID TUNNEL-LIKE PASSAGE MEANS BEING PROVIDED WITH PASSAGES EXTENDING THROUGH SAID BOTTOM MEMBER AND HAVING THEIR AXES SUBSTANTIALLY PERPENDICULAR THERETO. 